Die for drawing sheet metal



(N'o Model.)

fu, e Dv h s m e e h S No. 460,551. Patented 001'.. 6, 1891.

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DIE FOR DRAWING SHEET METAL.

No.v 460,551. Patented Oct. 6, 1891..

2186K? es directions-that is to say, I first draw the UNITED STATESPATENT OFFICE.

JOHN IV. BODGE, OF CHICAGO, ILLINOIS, ASSIGNOR TO OLIVER IV. NORTON, OFSAME PLACE, AND EDWIN NORTON,KOF MAYWOOD, ILLINOIS.

DIE FOR DRAWING SHEET METAL.'

SPECIFICATION forming part 0f Letters Patent N O. 460,551, dated October6, 1891.

Application led December 27, 1890. Serial No. 375.935. (No model.)

To aZZ whom it may concern: v

Be it known that I, JOHN IV. BODGE,a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented a new and useful Improvement in Dies for Drawing Sheet Metal,of which the following is a specification.

My invention relates to improvements in dies for drawing or stampingsheet metal into cylindrical, cup, or-disk shape forms.

I-Ieretofore great difiiculty has been experienced in drawing tin-plateor other metal sheets into cylindrical or cup shaped articles of anyconsiderable depth or length. IIeretofore this has been done by drawingthe sheet metal entirely in one and the same direction by suitabledrawing-dies constructed for the purpose, several sets of dies, eachsuccessivelyvsmaller than the preceding set, being employed to producearticles of any particular depth or length. In this old method ofdrawing there is great liability to stretch and crack or break thestock, and thus produce defective articles. The percentage of loss fromthis source is so great that it is customary to select the best,softest, and heaviest stock for the purpose, and even then there isalways a large percentage of failures where the articles to be drawnhave any considerable depth or length. i

The object of my invention is to provide dies for drawing sheet metalinto cylindrical shape, cup shape, disk shape, or other forms bymeansvof which the work may be easily, successfully, and rapidly donewithout danger of cracking or breaking the stock, and thus producingdefective articles.

I have discovered thatvtin-plate or other sheet metal may be readily andcheaply drawn into cylindrical or cup shape forms without danger ofcracking or breaking the stock by drawing it successively in diiferentplain sheet into a shallow cup or disk shape in one direction, and Ithen turn this shallow cup inside out by drawing it in the oppositedirection into a deeper cup of smaller diameter, which may be againturned inside out by drawing in the reverse direction, and thus producea cup or vessel of still greater depth and still smaller diameter. Bysuccessively reversing the direction in which the drawing is done, thussuccessively turning the vessel inside out, the sheet metal may beeasily and successfully drawn into cylinders or cones of any suitable ordesired depth or length and without danger of breaking or cracking thestock at any point. The means which I employ to thus reverse thedirection of the drawing and turn the vessel first drawn inside outconsists, in connection with a punch or male die of the required form tofit inside the smaller tube to be produced, of an annu# lar dieoperating in conjunction with said punch, the exterior periphery of thisannular die fitting inside the tube or vessel which is to be drawn intothe smaller tube by turning it inside out. The punch operating inconjunction with this annular die thus causes the stock to flow, turn,or be drawn around the annular shoulder of the annular die. In otherwords, the stock Viiows from the outer periphery of the annular die tothe inner periphery thereof, the outside tube fitting on the outside ofthe annular die, while the inside tube produced iits against the innerperiphery or wall of the annular die. By this means the drawingoperation is much facilitated, as the stock seems to naturally iiow orcurve around the annular corner which unites the outside large tube withthe inside small tube in the process of drawing the large tube into thesmall tube. The tendency also seems to be to compact the metal uponitself and rather to close the pores in the metal than to separate thesame and produce flaws or cracks therein.

In the accompanying drawings,which form a part of this specification, Ihave shown at Figures l, 2, 3, ,4, 5, and 6 adisk of tin-plate in 9oseveral successive stages of being drawn into a cylindrical-shaped cup.The cutting of the disk shown in Fig. l and the drawing of it into theform shown in Fig. 2 are performed by the ordinary drawing and cuttingdies now in use. 'Io render the nature of myimprovement in drawing-diesmore clearly understood,I have shown at Fig. 7 a sectional view of theseold drawing and cutting dies. Figs. S and 9 are sectional views of myimproved drawing-dies, the same being represented in different positionsand of different sizes, the

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size shown in Fig. 8 being that used to draw the cup shown in Fig. 2into the form shown in Fig. 4, and the size shown in Fig. 9 being thatused to draw the cup shown in Fig. fl into that shown in Fig. 6. Figs.10, 11, 12, and 13 show the form of: my improved dies which I use fordrawing conical'shaped articles. Fig. 1i is a sectional viewillustrating the operation of drawing a larger tube into a smaller tube.

In the drawings, A represents a blank of sheet met. l-for example,tin-plate.

A represents a shallow cup as produced by the ordinary drawing andcutting dies B, B', and B2 now commonly in use. The drawing and cuttingdies B B B2 have the usual follower or presser ring band ejector b. Thefollower-rin g b is supported in the usual manner by pins b2 on a rubberor other spring b3. After the shallow cup A is formed in the usual wayby the use of these old dies or other instrumentality it is ready foroperation upon my new drawing-dies, which operate to reverse this cup Aor turn it inside out and draw it in the opposite direction into thedeeper vessel A2, of smaller diameter.

My new reversing drawing-dies consist of a punch or male die C and anannular ifemale die C. The exterior diameter of the annular die Ccorresponds to the interior diameter of the shallow cup A', which is tobe reversed or turned inside out, and the interior diameter of theannular die C corresponds to the exterior diameter of the smaller cup orvessel A2, so that the cylindrical side or wall ct of the larger vesselmay flow or turn around the edge or face e of this annular die C', andthus unite with and form the cylindrical side or wall a2 ot' the smallerand deeper cup A2, produced by these dies. This operation is illustratedin Fig. 3, and also in the sectional view of the dies, Figs. S, 9, 10,11, 12, and 13.

The reversing-dies C C', which operate to turn a vessel previously drawninside out, and thus produce a deeper vessel of smaller diameter, areprovided with the customary follower or presser ring C2, which issupported in the usual way upon pins C, form a rubber or other springC4. The dies C C are also furnished with the usual ejector or plungerG5. The dies are operated in a press of any suitable forin orconstruction known to those skilled in the art, just the same asordinary dies, and I have not therefore thought itnecessary to hereinshow or describe the press, as the press forms no part of my presentimprovement. My dies C C may be applied to any press.

rlhe operation illustrated in FiU. 3, w.and which is performed by thereversing-dies C C', may be indeiinitely repeated byduplicate sets ofdies C C', of smaller and smaller diameter. In Fig. 9 I have shown onesuch duplicate set of dies of smaller diameter, the same operating toreverse the cup A2, (shown in Fig. 4,) and by turning' it inside outdraw it into the smaller cup. (Shown in Fig. 6.) This smaller cup isrepresented in the drawings at A3 and its cylindrical side or wall ata3.

In the act of turning, iiowing, or drawing the larger outside tube orvessel into the smaller inside tube or vessel an annular curved shouldera is formed between the two tubes a and 0.2 or a2 and a3, and whichunites the two tubes, and it is at this point that the work is done.Owing to the pulling or drawing of the two tubes a a2 in oppositedirections, as is clearly illustrated in the diagram view,Fig. 14, andowing, also, to the curved annular shoulder a, uniting the larger andsmaller tubes, it will readily be understood by those skilled in the artthat the operation is a peculiarly easy and natural one, requiring acomparatively small amount of force and tending rather to compact themetal and close its pores than to crack or break or injure it. Incurving or drawing the larger tube into the smaller one the curvedshoulder a between the two tubes seems to act in the nature oi aleverage, and thus to facilitate or render easy the drawing operation.In the act of drawing-the larger tube into the smaller one, the outsideperiphery of the annular drawing tool or die C serves to support thestock of the larger tube, which fits upon it, and to keep it smooth andcause it to flow or draw in proper lines. The annular shoulder or face cof the annular die C is or should be made curved or rounded tofacilitate the turning of the stock around it. This rounded shoulder ealso serves to support and guide the stock in the act of flowing ordrawing from the larger tube into the smaller one.

In Figs. 10, 11, 12, and 13 the invention is illustrated as applied tothe drawing of conical or flaring vessels, the same being also left witha horizontal flange at, as shown in Fig. 13. rIhe dies used in theseIigures only differ from those shown in Figs. S and f) by being madeconical. Figs. 10 and 11 show the same pair of dies in differentpositions. Those shown in Figs. 12 and 13 are the same, excepting thatthe interior diameter of the hollow conical die and also its punch aresomewhat smaller than those shown in Figs. 10 and 11. The use of twoseparate pairs of dies, where the dies are conical, to draw the cupshown in Fig. 10 into the shape shown in Fig. 13 is simply to bettersupport the stock. If the small die shown in Figs. 12 and 13 wereapplied directly to the cylindrical cup shown in Fig. 10, there would betoo much space left between the small end of the conical punch and thelarger interior diameter of the hollow conical annular die to do thebest work. For this reason I employ two sets of dies for performing oneoperation where the articles to be drawn have any considerable flare.

The die C', I call an annular die,as both its outside periphery or wallc and its inside periphery or wall c2 are operative and serve to guideand support the flowing, turning, or

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drawing of the metal, as does also the annular shoulder or end c of thisdie. In ordinary dies heretofore in use only the end and inner peripheryofthe die are operative-as shown, for example, in Fig. 7.

I claiml. The sheet-metal-drawing dies for turning a vessel orshapeinside out and drawing it into a vessel or shape of smallerdiameter, consisting of a punch or male die C and an annular die C',upon the outer periphery of which the vessel to be reversed or turnedinside out fits, substantially as speeied.

2. The sheet-metal-drawing dies for turning a vessel or shape inside outand drawing it into a vessel or shape of smaller diameter, consisting ofa punch or male die C and an annular die C', upon the outer periphery ofwhich the vessel to be reversed or turned inside out fits, said annulardie C having a rounded edge or shoulder c, substantially as speoied.

3. The sheet-metal-drawing dies for turning a vessel or shape inside outand drawing it into a vessel or shape of smaller diameter,

consisting of a punch or male die C and an annular die C', upon theouter periphery of which the vessel to be reversed ts, and a follower orpresser C2,substantial1y as speeiiied.

JOHN W. BODGE. W'itnesses:

W. C. ToLEs, H. N. NORTON.

